Sub Luna Support

Last Updated: April 18, 2026

Sub Luna is a Safari extension that brings zero-flash dark mode and curated themes to every website. This page covers how to get it working and how to reach us.

Your Data Stays on Your Device

Sub Luna makes zero network connections. No analytics, no crash reporting, no update checks, no third-party SDKs, no server of any kind. The app and the Safari extension run 100% on-device.

The only data Sub Luna stores is what you choose: your theme preference, brightness, schedule, and per-site overrides. It lives in the shared App Group on your device, and — when you're signed into iCloud — syncs privately between your own Apple devices through Apple's key-value store. We cannot see the contents.

If you're used to other dark-mode extensions that phone home or change ownership, you can verify our claim yourself: run Sub Luna with Little Snitch, Charles, or any network monitor filtered to our bundle IDs (com.jameshuangstudio.subluna / com.jameshuangstudio.subluna.extension). You'll see nothing.

For the full statement, see our Privacy Policy.

Contact

For questions, bug reports, or feature requests, email us at support.jamesstudio@gmail.com. We typically respond within 2 business days.

Enabling the Extension

On iPhone / iPad

Open the Settings app and go to Apps → Safari → Extensions.
Tap Sub Luna and turn it on.
Tap All Websites and choose Allow.
Return to Safari. The extension is now active.

On Mac

Open Safari, choose Safari → Settings → Extensions.
Check the box next to Sub Luna.
When prompted, grant access to all websites.

Frequently Asked Questions

The page still looks light after I enabled the extension.

First, reload the page. If the site is still light, open Sub Luna's popup in the Safari toolbar and confirm that dark mode is set to On or Auto. If the site is excluded, check Site Settings inside the Sub Luna app.

Can I use a different theme on different websites?

Yes. Open the Sub Luna app, go to Site Settings, and assign any built-in or custom theme on a per-site (or per-path) basis. The longest matching path wins.

Do my custom themes sync across devices?

Yes. Custom themes sync through your personal iCloud account across devices signed into the same Apple ID. See the Privacy Policy for details on what is and is not synced.

Does Sub Luna collect my browsing data?

No. Sub Luna does not collect, transmit, or store any browsing data, personal information, or usage analytics. Everything runs on-device. See the Privacy Policy for the full statement.

The floating toggle button is in the way.

Open the Sub Luna app, go to General, and turn off Floating Toggle.

A specific site looks broken in dark mode.

Open Site Settings, add the site, and either switch to a gentler theme or set it to Off to leave that site untouched. If you'd like us to improve automatic handling for that site, email us the URL.